Author(s): Iago Q. Silva; Alexandre K. Soares; Joel R. G. Vasco
Linked Author(s):
Keywords: Hydraulic transients; MOC; CSPM; Artificial viscosity; Meshfree methods; Normalization; Shepard's interpolation
Abstract: Hydraulic transients are phenomena that occur when the conditions of a flow, such as pressure and velocity, change with time. This regime may not be calculated by explicit solutions. Therefore, it is necessary to use numerical methods, amongst which the method of characteristics (MOC) stands out. The MOC uses a characteristic grid to transform partial differential equations (PDEs) into ordinary differential equations (ODEs). However, as other grid based methods, it may present some problems, especially when there are complex geometries and deformable contours. To solve these problems, there are methods that don’t use grids (meshfree), amongst which the corrective smoothed particle method (CSPM) stands out. This method allows that a function and its derivatives may be represented by an approximation. To apply it to a hydraulic transient, it is necessary to make an adaption by considering a term known as artificial viscosity, besides using a temporal integration method. In this paper, in order to verify the efficiency of methods with or without grids, a hydraulic transient was simulated using MOC and CSPM. The results showed that CSPM produces values that are compatible with MOC, although there are little divergences as the simulation runs. Besides, an analysis was conducted to verify the influence of the normalization of velocity and pressure in CSPM.
Year: 2025